Parwal,
You should first verify that the default policy definitions have been configured for the AllDevicesGroup. In the Central Manager, go to:
My WAN > Device Groups > AllDevicesGroup > Configure > Acceleration > Policy Defintions
If there are no application policies listed, click the Restore Default Policies and Classifiers button. Once you have done this, or verified that there are application policies in place, you can ensure that the individual devices get their policy settings from the AllDevicesGroup by clicking the Force Group Settings button from the AllDevicesGroup home page.
If you have any additional questions, please let us know.
Regards,
Zach